title: A methodology for incorporating functional bone marrow sparing in IMRT planning for pelvic radiation therapy.
abstract: OBJECTIVE
  The purpose of this study was to design a radiation therapy treatment planning approach that would spare hematopoietically active bone marrow using [(18)F]FLT PET imaging.
  
  
  METHODS
  We have developed an IMRT planning methodology to incorporate functional PET imaging using [(18)F]FLT scans. Plans were generated for two simulated cervical cancer patients, where pelvic active bone marrow regions were incorporated as avoidance regions based on the ranges: SUV4 ≥ 4; 4>SUV3 ≥ 3; and 3 > SUV2 ≥ 2. Dose objectives were set to reduce bone marrow volume that received 10 (V(10)) and 20 (V(20))Gy.
  
  
  RESULTS
  Active bone marrow regions identified by [(18)F]FLT with an SUV ≥ 2, SUV ≥ 3, and SUV ≥ 4 represented an average of 43.0%, 15.3%, and 5.8%, respectively of the total osseous pelvis for the two cases studied. Improved dose-volume histograms for all identified bone marrow SUV volumes and decreases in V(10), and V(20) were achieved without clinically significant changes to PTV or OAR doses.
  
  
  CONCLUSIONS
  Incorporation of [(18)F]FLT PET in IMRT planning provides a methodology to reduce radiation dose to active bone marrow without compromising PTV or OAR dose objectives in pelvic malignancies.
authors.affiliation: Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA. sarah-mcguire@uiowa.edu
authors.forename: Sarah M
authors.initials: SM
authors.lastname: McGuire
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Menda
authors.forename: Laura L Boles
authors.initials: LL
authors.lastname: Ponto
authors.forename: Brandie
authors.initials: B
authors.lastname: Gross
authors.forename: Malik
authors.initials: M
authors.lastname: Juweid
authors.forename: John E
authors.initials: JE
authors.lastname: Bayouth
mesh_terms: D001853:Bone Marrow / Q000000981:diagnostic imaging* / Q000528:radiation effects*; D015224:Dideoxynucleosides; D005260:Female; D005462:Fluorine Radioisotopes; D006801:Humans; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D002583:Uterine Cervical Neoplasms / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D051598:Whole Body Imaging
chemical_list: D015224:Dideoxynucleosides; D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals